The majority of PV cells produced today use crystalline silicon (c-Si) as it is a light absorbing semiconductor. The c-Si technology was originally developed for the semiconductor industry to produce PV cells for integrated circuits and microchips. These PV cells have energy conversion efficiencies between 11 percent and 16 percent. The energy conversion efficiency of a solar cell is the percentage of incident sunlight converted into electricity. While the efficiency of c-Si is high, it absorbs light poorly and requires many layers to perform efficiently in solar applications.

The two types of crystalline silicon technologies used to produce PV cells are mono and multi-crystalline (also called poly-crystalline).

A polycrystalline cell is cut from a multifaceted silicon crystal. More surface area is required due to inherent flaws and these panels are less efficient in converting the sun's rays. However, a polycrystalline cell per watt is usually 15% cheaper than mono-crystalline cell.